Disposable packages for flexible synthetic resin containers

ABSTRACT

A disposable package having a plurality of flexible-wall synthetic-resin receptacles, e.g., milk or other bulk-material receptacles of the bag type (nonselfsupporting or collapsible), consists of a heat-sealed skin drawn snugly around the receptacle. The skin is preferably a bottom-fold or side-fold enclosure composed of an opaque synthetic-resin foil and may be charged with nitrogen to reduce deterioration of the packaged contents.

United States Patent 1191 3,764,000 Jentsch 1 Oct. 9, 1973 DISPOSABLE PACKAGES FOR FLEXIBLE 3,521,806 7/1970 Esty 206/46 PV SYNTIWTIC-REYSIN CONTAINERS FOREIGN PATENTS OR APPLICATIONS [76] Inventor: Hans G. Jentsch, Darmlerstrasse 4, 1,814,100 6/1970 Germany.... 206/65 S Essen, Germany Primary Examiner-William T. lDixson, Jr. [22] Filed. June 28, 1971 An0mey Karl E Ross [211 App]. No.: 157,331

' [57] ABSTRACT 52 us. Cl 206/65 R, 206/46 PV, 229/61 A disposable Package having a plurality of flexible- 51 Int. Cl 865d 85/62 wall synthetic'resin receptacles, -'g-, k or other 58 Field Of Search 206/65 s, 65 R, 45.33, bulk-material receptacles of the bag yp p- 29 /4 pv; 229 1 57 porting or collapsible), consists of a heatsealed skin drawn snugly around the receptacle. The skin is pref- 5 References Cited erably a bottom-fold or side-fold enclosure composed UNITED STATES PATENTS ofv an opaque synthetic-resin foil and may be charged with nitrogen to reduce deterioration of the packaged 3,458,036 7/1969 James 206/65 S contents 2,339,305 H1944 Wagner 229/61 3,136,475 6/ 1964 Geimer 229/57 8 Claims, 3 Drawing Figures A n-"1 s 2 PATENTEU OUT 9 5 Hans G. Jenfsch INVENTOR s Attorney DISPOSABLE PACKAGES FOR FLEXIBLE SYNTHETIC-RESIN CONTAINERS FIELD OF THE INVENTION BACKGROUND OF THE INVENTION In recent years, interest has been generated in packages which create less of an environmental hazard, which are more readily handled and stored and which havegreat strength and are capable of maintaining the quality of a packaged substance over long periods. For example, this period has seen a replacement of the metal,can,.glass jar, bottle or jug by paper or syntheticresin containers for liquids, pasty material and granular substances, in order to reduce breakage, to lower deadweight which must be transported, to increase the closeness with which individual packaging unitsmaybe stored and stacked, to eliminate return trips, and to improve the ability of the purchase to handle the packaged product. In fact, even these relatively rigid-wall containers are being increasingly displaced by flexible wall or collapsible receptacles, generally of a syntheticresin foil, and describable as synthetic-resin tubes, bags, pouches or sacks. Such receptacles have been used, as indicated, for liquid, pasty or granular products, all of which are flowable, and a prime example is the use of flexible-wall pouches in the distribution and packaging of milk. These containers are nonselfsupporting.

To facilitate the transportation, delivery and storage of flexible-wall receptacles of the character described, i.e., collapsible containers, it has been proposed to provide-delivery trays or cases formed with seats, projec tions and the like designed to accommodate the individual receptacle. These cases, however, create other problems which will be readily apparent. For example, when the receptacles contain comestibles, the cases must be returned to the packing installation, washed or otherwise cleaned, and returned to the distribution cycle for reasons of economy. Generally, the receptacles must have a minimum volume and weight so as to possess the required strength for stacking, transportation and re-use so that the transportation costs are increased.

OBJECTS OF THE INVENTION It is the principal object of the present invention to provide a packaging system in which the aforementioned difficulties can be obviated.

Another objectofthe invention is to provide a package, containing two or more such flexible-wall receptacles, which can be stacked and handled readily, is of low cost, is capable of maintaining the quality of the packaged product, and is self-standing.

SUMMARY OF THE INVENTION ages after the latter have been inserted through the open upper side.

According to the invention, when the package skin, preferably of a thermoplastic synthetic resin foil, is a bottomfold and/or side-fold enclosure provided with side walls to define a flat bottom, a pair of upright mutually parallel endwalls and a pair of mutually parallel side walls spaced apart by the end wall and perpendicular thereto and to the bottom, two or more flexible-wall containers canbe introduced and the flexible foil or skin drawn tightly around the enclosed containers.

Then the upper end can be sealed, preferably with a welded or heat-sealed seam. The heat-sealing process preferably employs separation-welding techniques whereby unwanted material, superfluous flaps or foil resulting from the tightening of the foil around the enclosed containers, is removed along those portions of the foil which may be employed subsequently for en- ,casing the container. The enclosure may have a width less than the normal width of the containers so that the latter stretch the enclosure walls to generate the desired tension.

Advantageously, at least one side of the outer package is provided with a fold or web unitarily joining opposing walls while other sides may be formed by heatsealing the system into a rectangular parallelopipedal configuration. Surprisingly, a tightening of the skin around the flexible-wall containers appears to rigidify the entire structure and render the same freestanding and stackable.

According to another feature of the invention, hte

outer packaging foil is composed of an opaque or lightimpermeable material by compounding a pigment or the like into the synthetic resin prior to extrusion of the foil. The coloration of the foil may be selected in accor dance with esthetic considerations, although total light blockage is desirable. In this manner, the disposable foil can be cut away or torn away from the inner condensers but prevents deterioration of the contents of these containers when in place. The foil provides mechanical protection as well as stability, reduces the oxygen penetration into the containers.

It has also been found to be advantageous to flush the outer package with nitrogen or to introduce nitrogen into the pacakge prior package sealing, thereby driving out any oxygen which may have been present. A high nitrogen concentration within the package reduces the tendency for oxygen to diffuse into the inner contain-.

ers.

The system of the present invention also has the advantage that the outer layer of packaging material is fully sealed and serves as an additional protection against leakage from the inner containers. All in all, therefore, the food products or the like packaged with the present system have an improved shelf life. In the case of milk in which 2, 3 of 4 quarts or liters areenclosed in a single package, it has been found that the packages can be stacked in five or six levels without supporting shelves, guides or the like and can be carried by pellets. Of course, horizontal stacking in larger 1 numbers is possible and one may resort to a larger I have discovered that the aforementioned disadvan- I tages canbe eliminated and that strong, freestanding, stackable packages can be made by employing an outer skin of rectangular parallelopipedal configuration formed tightly around two or more flexible-wall packstacking arrangement in which each shelf carries five to six levels of packages. The system can be produced in conventional filling machines provided with means for gouping the inner containers in the desired numbers (e.g two, three or four) automatically. The groups of containers can be introduced into upwardly open disposable packages of the character described, the foil being drawn tightly around the containers by mechanical means. The walls of the outer packages may be held under tension during the entire packaging operation and then sealed by impulsive welding techniques. Wastes and foil excesses may be removed simultaneously. The sealing of the upper wall of the outer package may simultaneously provide a flap which can constitute a handle.

DESCRIPTION OF THE DRAWING The above and other objects, features and advantages of the present invention will become more readily apparent from the following description, reference being made to the accompanying drawing in which:

FIG. 1 is a perspective view of a synthetic resin foil package embodying the present invention;

FIG. 2 is a fragmentary detail view, partly broken away, of a corner of the package of FIG. 1; and

FIG. 3 is a detail view of the top wall of another package according to the invention.

SPECIFIC DESCRIPTION In FIG. I, I have shown a package 1 of a syntheticresin foil, which is fully sealed in a fluid-tight manner, has been closed after introduction of nitrogen, and is composed of a opaque thermoplastic material, preferably black, dark green or dark blue polyethylene. The foil may have a thickness of the order of a millimeter or a fraction thereof. The rectangular parallelopipedal outer foil 1 receives three liquid-filled, flexible-wall, collapsible synthetic-resin tubular sacks 11 which need not be self-standing or even stackable. Such sacks have been provided heretofore for the distribution of milk.

The package 1 comprises a bottom wall 2 which is unitary with a pair of lateral walls 12 and 13 while being connected with them at simple bends l4 and 15. The walls 12 and 13 have an upwardly open mouth at 3 through which the containers 11 are inserted and which is closed by a weld seam 9 formed between a pair of flaps l6 and 17, unitarily connected at bends l8 and 19 with the walls 12 and 13. The end walls of the outer package are formed with vertical weld seams 8 along flaps 20 and 21, unitarily secured by bends 22 and 23 to the walls 12 and 13. The end walls are, .of course, perpendicular to the walls 12, l3, l5, l6 and 2.

At the bottom corners, there are formed gussets or pockets of triangular configuration at 6 and 7 which are turned inwardly and are welded to the outer walls at points 10. As can be seen from FIG. 2, each of these pockets has a triangular inner wall 24 bent upwardly at 6 from the bottom wall 2, and a pair of triangular flaps 25, 26 welded at 27 and respectively turned upwardly at 7 to form the flaps 20 and 21. The gussets at the upper end of the package form ears 4 and are also of triangular configuration. These ears may be gripped by the user to serve as handles. When the packages are stacked, the ears are simply bent downwardly onto the upper wall l6, 17. Alternatively, the welding operation may provide a handle as shown at 26 in FIG. 3. In either case, the package is completely sealed and stretched into rectangular parallelopipedal configuration with the individual containers 11 being combined under the tension produced by the stretching of the foil. In the illustrated embodiment, three containers have been shown to be provided within the package. It is, of course, possible to use fewer or larger numbers as desired.

The tension with which the package retains the containers may be produced by dimensioning the width of the bottom 2 and the end walls 20, 21 to be slightly less than the width of the group of containers prior to their introduction into the enclosure forming the package. The foil of the enclosure is thereby stretched. Preferably, the enclosure is sealed (heat-sealed) along a seam directly above the containers.

I claim:

I. A package comprising a plurality of flexible-wall containers for flowable substances in abutting relationship, and a disposable synthetic-resin-foil enclosure stretched tightly around said containers, said enclosure having a plurality of pairs of mutually parallel walls and being thermally sealed directly above said containers, said enclosure having a bottom wall, a pair of mutually parallel end walls perpendicular to said bottom wall, a pair of mutually parallel side walls perpendicular to said end walls and said bottom walls, and a top wall formed by a pair of flaps and thermally sealed together to close the enclosure, said top and end walls defining respective outwardly projecting ears facilitating manipulation of the package.

2. The package defined in claim 1 wherein said bottom, end and top walls have widths less than that of the containers prior to insertion of the containers into said enclosure whereby said walls are maintained under tension against said containers.

3. The package defined in claim 2 wherein said end walls and said bottom wall define respective gussets folded into said enclosure and thermally welded to said end walls.

4. The package defined in claim 3 wherein said enclosure is composed of an opaque foil.

5. The package defined in claim 3 wherein said enclosure is charged with nitrogen.

6. The package defined in claim 3 wherein said containers are arrayed in a row, said seam extending along said row.

7. A method of making a package, comprising the steps of forming an upwardly open side-fold or bottomfold enclosure having a width less than that of a container to be packaged; inserting a plurality of such containers into said enclosure, thereby stretching the walls thereof; closing said enclosure while drawing the same tightly around said containers by thermally welding the enclosure simultaneously with removal of excess material therefrom; and forming ears on said container to facilitate gripping same.

8 The method defined in claim 7, further comprising the step of charging said enclosure with nitrogen prior to sealing same. 

1. A package comprising a plurality of flexible-wall containers for flowable substances in abutting relationship, and a disposable synthetic-resin-foil enclosure stretched tightly around said containers, said enclosure having a plurality of pairs of mutually parallel walls and being thermally sealed directly above said containers, said enclosure having a bottom wall, a pair of mutually parallel end walls perpendicular to said bottom wall, a pair of mutually parallel side walls perpendicular to said end walls and said bottom walls, and a top wall formed by a pair of flaps and thermally sealed together to close the enclosure, said top and end walls defining respective outWardly projecting ears facilitating manipulation of the package.
 2. The package defined in claim 1 wherein said bottom, end and top walls have widths less than that of the containers prior to insertion of the containers into said enclosure whereby said walls are maintained under tension against said containers.
 3. The package defined in claim 2 wherein said end walls and said bottom wall define respective gussets folded into said enclosure and thermally welded to said end walls.
 4. The package defined in claim 3 wherein said enclosure is composed of an opaque foil.
 5. The package defined in claim 3 wherein said enclosure is charged with nitrogen.
 6. The package defined in claim 3 wherein said containers are arrayed in a row, said seam extending along said row.
 7. A method of making a package, comprising the steps of forming an upwardly open side-fold or bottom-fold enclosure having a width less than that of a container to be packaged; inserting a plurality of such containers into said enclosure, thereby stretching the walls thereof; closing said enclosure while drawing the same tightly around said containers by thermally welding the enclosure simultaneously with removal of excess material therefrom; and forming ears on said container to facilitate gripping same.
 8. The method defined in claim 7, further comprising the step of charging said enclosure with nitrogen prior to sealing same. 